On Thu, Jun 11, 2015 at 01:54:22PM +0800, Jason Wang wrote: > > > On 06/11/2015 01:49 PM, Thibaut Collet wrote: > > > Yes, but still need a mechanism to notify the backend of migration > > > completion from qemu side if GUEST_ANNOUNCE is not negotiated. > > > > backend is aware of a connection with the guest (with the feature > > negociation) and can send a rarp. This rarp will be always sent by the > > backend when a VM is launched (first start or live migration > > completion) if the GUEST_ANOUNCE is not supported. > > In this case the issue is solved without done everything by QEMU. > > The issue is during migration guest network is still active. So sending > rarp too early in the destination (e.g during VM is launched) may > confuse the switch. We want it to be sent exactly when the migration is > completed in destination.
It needs to be sent when backend is activated by guest kick (in case of virtio 1, it's possible to use DRIVER_OK for this). This does not happen when VM still runs on source. > > If sending a rarp message on the start of te VM is not accceptable, we > > must provide a mechanism similar of the one I have implemented. The > > message content can be empty as the backend is able to create the rarp > > message. > > Yes.
